While wireless sensor networks (WSN) are increasingly equipped to handle more complex functions, in-network processing still requires the battery powered sensors to judiciously use their constrained energy so as to prolong the efective network life time. There are a few protocols using sensor clusters to coordinate the energy consumption in a WSN. To cope with energy heterogeneity among sensor nodes, a modified clustering algorithm is proposed with a three-tier sensor nodes setting. This approach is an improvement to the original SEP protocol that used two-tier node setting. The result showed a better management of energy resource than both LEACH and SEP.
In addition, two forms of extensions to LEACH algorithm, multi-hop and dual-hop LEACH algorithms using a concentric circle around the BS, are presented. The goal of these methods is to analyze the adaptation of different communication modes to the original LEACH protocol that used a single-hop communication mode among its sensor nodes. This thesis further carried out a spatial distribution of energy-based comparative study of homogeneous and heterogeneous clustered WSN. The study revealed a new approach for analyzing the performance of wireless sensor network protocol designs. Simulation has been conducted to evaluate these new approaches and favorable results are obtained in both homogeneous and heterogeneous energy settings.
